Alkylation of aromatic hydrocarbons



United States 2,939,890 Patented June 7, 1960 2,939,890 ALKYLATION orAROMAIIC HYnRooARsoNs N Drawing. Filed Mar. 18, 1958, Ser. No. 722,121

19 Claims. (Cl. 260-671) This invention relates to a process for thealkylation of aromatic hydrocarbons, and more particularly relates to aprocess for the alkylation of aromatic hydrocarbons with olefin-actingcompounds in the presence of a catalyst comprising a boron trifluoridemodified substantially anhydrous inorganic oxide. Still moreparticularly this invention relates to a process for the alkylation ofaromatic hydrocarbons with olefin-acting compounds in the presence of acatalyst comprising boron trifluoride and boron trifluoride modifiedsubstantially anhydrous gammaor theta-alumina.

An object of this invention is to produce alkylated aromatichydrocarbons, and more particularly to produce benzene hydrocarbons. Aspecific object of this invention is to produce ethylbenzene, a desiredchemical intermediate, which is utilized in large quantities indehydrogenation process for the manufacture of styrene, one startingmaterial in the production of some synthetic rubbers. Another specificobject of this invention is a process for the production of cumene bythe reaction of benzene with propylene, which cumene product may beoxidized to form cumene hydroperoxide, which latter compound is readilydecomposed into phenol and acetone. Another object of this invention isthe production of para-diisopropylbenzene, which diisopropylbenzeneproduct is oxidized to terephthalic acid, one starting material for theproduction of some synthetic fibers. A further specific object of thisinvention is to produce alkylated aromatic hydrocarbons boiling withinthe gasoline boiling range having high antiknock value and which may beused as such or as components of gasoline suitable for use in automobileengines. Still another object of this invention is the alkylation ofaromatic hydrocarbons with so-called refinery olT-gases or dilute olefinstreams, said olefin-containing streams having olefin concentrations inquantities so low that such streams have not been utilizedsatisfactorily as alkylating agents in existing processes without priorintermediate olefin concentration steps. This and other objects of theinvention will be set forth hereinafter in detail as part of theaccompanying specification. 7

Previously, it has been suggested that boron trifluoride can be utilizedas a catalyst for the alkylation of aromatic hydrocarbons withunsaturated hydrocarbons. For example, Hofmann and Wulfi succeeded inreplacing aluminum chloride by boron trifluoride for catalysis ofcondensation reactions of the Friedel-Crafts type; (German Patent513,414, British Patent 307,802, and French Patent 665,812). Aromatichydrocarbons such as benzene, toluene, tetralin, and naphthalene havebeen condensed with ethylene, propylene, isononylene, and cyclohexene inthe presence of boron trifluoride with the production of thecorresponding monoand polyalkylated aromatic hydrocarbon derivatives. Inthese processes rather massive amounts of boron trifluoride have beenutilized as the catalyst. Similarly, the olefin utilized has been pureor substantially pure. No successful processes have yet been introducedin which the olefin content of a gas stream, which is rather dilute inolefins, has been successfully consumed to completion in the absence ofsome olefin concentration step or steps. By the use of the process ofthe present invention, such gas streams may be utilized per se asalkylating agents along with minor amounts of boron trifluoride andsubstantially complete conversions of the olefin content are obtained.

One embodiment of this invention relates to a process for the productionof an alkylaromatic hydrocarbon which comprises passing to an alkylationzone containing a boron trifluoride modified substantially anhydrousinorganic oxide, alkylatable aromatic hydrocarbon, olefinactingcompound, and not more than 0.8 gram of boron trifluoride per gram molof olefin-acting compound, reacting therein said alkylatable aromatichydrocarbon with said olefin-acting compound at alkylation conditions inthe presence of an alkylation catalyst comprising said boron trifluoridemodified substantially anhydrous inorganic oxide, and recoveringtherefrom alkylated aromatic hydrocarbon.

Another embodiment of this invention relates to a process for theproduction of an alkylbenzene hydrocarbon which comprises'passing to analkylation zone containing boron trifluoride modified substantiallyanhydrous gamma-alumina, alkylatable benzene hydrocarbon, olefin, andnot more than 0.8 gram of boron trifluoride per gram mol of olefin,reacting therein said alkylatable benzene hydrocarbon with said olefinat alkylation conditions in the presence of an alkylation catalystcomprising said boron trifluoride modified substantially anhydrousgamma-alumina, and recovering therefrom alkylated benzene hydrocarbon.

Still another embodiment of this invention relates to a process for theproduction of an alkylbenzene hydrocarbon which comprises passing to analkylation zone containing boron trifluoride modified substantiallyanhydrous theta-alumina, alkylatable benzene hydrocarbon, olefin, andnot more than 0.8 gram of boron trifluoride per gram mol of olefin,reacting therein said alkylatable benzene hydrocarbon with said olefinat alkylation conditions in the presence of an alkylation catalystcomprising said boron trifluoride modified substantially anhydroustheta-alumina, and recovering therefrom alkylated benzene hydrocarbon.

A specific embodiment of this invention relates to a process for theproduction of ethylbenzene which comprises passing to an alkylation zonecontaining boron trifluoride modified substantially anhydrousgamma-alumina, benzene, ethylene, and from about 0.001 gram to about 0.8gram of boron trifluoride per gram mol of ethylene, reacting thereinsaid benzene with said ethylene at alkylation conditions. including atemperature of from about 0 to about 300 C. and a pressure of from aboutatmospheric to about 200 atmospheres in the presence of an alkylationcatalyst comprising said boron trifluoride and boron trifluoridemodified substantially anhydrous gamma-alumina, and recovering therefromethylbenzene.

A still further specific embodiment of this invention relates to aprocess for the production of cumene which comprises passing to analkylation'zone containing boron trifluoride modified substantiallyanhydrous gammaalumina, benzene, propylene, and from about 0.001 gram toabout 0.8 gram of boron trifluoride per gram mol of propylene, reactingtherein said benzene with said propylene at alkylation conditionsincluding a temperature of from about 0 to about 300 C. and a pressureof from about atmospheric to about 200 atmospheres in the presence of analkylation catalyst comprising said boron trifluoride and borontrifluoride modified substantially anhydrous gamma-alumina, andrecovering therefrom cumene. i

We have found, when utilizing a catalyst comprising a boron trifluoridemodified substantially anhydrous inorganic oxide, that the alkylation ofaromatic hydrocarbons with olefin-acting compounds is surprisingly easywhen boron trifluoride is suppliedin a quantity not greater than 0.8"gram of boron trifluoride per gram mol of olefin-acting compound. Thequantity of boron trifluoride utilized may be appreciably less than 0.8gram per gram mol of olefin-acting compound and conversion of theolefin-acting compound to alkylaromatic hydrocarbon still observed. Whenthe quantity of boron trifluoride utilized is greater than about 0.8gram per gram mol of olefin-acting compound, side reactions begin to,take place which convert the olefin-actingv compound to other than thedesired-alkylaromatic hydrocarbon. With introduction of the borontrifluoride. into the reaction zone in an amount within the range of0.00'l'j gram to,0.8' gram per gram moi of olefin-acting compound.substantially complete conversion of the olefin-acting'compound isobtained to produce desired alkylaromatic hydrocarbons, even, whentheolefin-acting compound is-present as a so-called diluent in a gasstream the other components of which are inert under the reactionconditions and which other components decrease the partial pressure ofthe olefin present in the alkylation reaction zone. Furthermore, we havefound that the use of a boron trifluoride modified substantiallyanhydrous inorganic oxide along with the limited quantities of borontrifluoride hereinabove described results in the attainment ofcompleteness of reaction which has not been possible prior to this time.Furthermore, when the boron trifluoride modified substantially anhydrousgammaor thetaalumina is present in the alkylation reaction zone, it hasbeen found that the boron trifluoride may be added continuously,intermittently, or in some cases addition may be stopped, provided, ofcourse, that the boron trifluoride added was never greater than 0.8 gramper gram mol of olefin-acting compound. Thus, the process may be startedwith boron trifluoride addition, for example,.within the above setforthranges, and the boron trifluoride addition discontinued. Dependingwhether or not the boron trifluoride modified substantially anhydrousgammaor theta-alumina retains its activity, it may or may not benecessary to add further quantities of boron trifluoride within theabove set forth ranges. This feature of the process of the presentinvention will be set forth more fully hereinafter.

Boron trifluoride is a gas (B.P. l01 C., M.P. 126 C.) which is readilysoluble in most organic solvents. It may be utilized per so by merelybubbling into a reaction mixture or it may be utilized as a solution ofthe gas in an organic solvent such as the aromatic hydrocarbon to bealkylated, for example, benzene. Such solutions are within the generallybroad scope of the use of a boron trifluoride catalyst inv the processof the present invention although not necessarily with equivalentresults. Gaseous boron trifluoride is preferred.

The'preferred catalyst composition, as stated hereinabove, comprisesboron trifluoride and boron trifluoride modified substantially anhydrousbut not completely dry alumina. Of the various types of alumina whichmay be successfully and satisfactorily modified with boron trifluoride,two crystalline structures of alumina have been found to be particularlysuitable. These crystalline structures are substantially anhydrousgamma-alumina and substantially anhydrous theta-alumina. The exactreason for the specific utility of these two crystalline aluminamodifications in the process of this invention is not fully understoodbut it is believed to be connected with the number of residual hydroxylgroups on the surface of these two particular crystalline aluminamodifications. It has been'established, for example, that othercrystalline alumina modifications such as gamma-alumina trihydrate (Al O-3H O) or anhydrous alpha-alumina are less active and cannot be utilizedin the process of this invention in the same manner as substantiallyanhydrous gammaalumina and substantially anhydrous theta-alumina areused whenever complete olefin consumption is required. h'iodification ofaiurninas with boron trifluoride may be carried out prior to theaddition of the alumina to the alkylation reaction zone or thismodification may be carried out in situ. Furthermore, this modificationof the alumina with boron trifluoride may be carried; out prior tocontact of these boron trifluoride modified aluminas with the aromatichydrocarbon to be alkylated and the olefin-acting compound, or themodification may be carried out in the presence of the aromatichydrocarbon to be alkylated, or in the presence of both the aromatichydrocarbon to be alkylated and the. olefinacting compound. Obviouslythere is some limitation upon this last mentioned method of aluminamodification. The modification of the above mentioned aluminas withboron trifluoride is an exothermic reaction and care must be taken toprovide for proper removal of theresultant heat. The modification of thealumina is carried out by contacting the alumina with from about 2% toaboutby weight boron trifluoride based on the alumina. In one manner ofoperation, the. alumina is'placedt as; a fixed bed in a reaction zone,which may be the alkylat'io'n: reaction zone, and the desired quantityof boron trifluoride is passed therethrough; In such a case, the boron'tr i. fluoride may be utilized in so-called massive amounts or may beused in dilute form diluted with various other gases such as hydrogen,nitrogen, helium, etc. This contacting is normally caried out at roomtemperature although temperatures up to that to be utilized for the:alkylation. reaction, that is, temperatures up to about 300 C. may beused. With the preselectedflalumina at' room temperature, utilizingboron trifluoride alone, a

temperature wave will travel through the alumina bed;

during this modification of the alumina with boron tri fluoride,increasing the temperature of the alumina from room temperature up toabout C. or more. As the' boron trifluoride content of the gases to bepassed over the alumina is diminished, this temperature increase alsodiminishes and can be controlled more readily, in such instances. Inanother method for the modification of the" above mentioned gammaandtheta-aluminas with boron trifluoride, the alumina may be placed as'afixed bedin the alkylation reaction zone, the boron trifluoride dissolved in the aromatic hydrocarbon to'be alkylated, and the solution ofaromatic hydrocarbon and boron t-rifluoride passed over the alumina atthe desired temperature until sufiicient boron trifluoride has modifiedthe alumina. When the gas phase treatment of the alumina is carried out,it is noted that no boron trifluoride passes through the aluminabeduntil all of the alumina has been modified by the boron trifluoride.This same phenomena is observed during the modification of the-aluminawith; the aromatic hydrocarbon solutions, containing boron trifluoride,In another method, the modification of the alumina can be accomplishedby utilizationof a mixture,

of aromatic hydrocarbon to be alkylated, olefin-acting compound, andboron trifluoride which upon passage over the alumina formsthedesired'boron trifluoride moth fled aluminain situ. In the lattercase, of course', the'=- activity of the system is low initially andincreases as the complete modification of the alumina with the borontrifluoride takes place. The exact manner' by which the borontrifluoride modifies the alumina is not un derstood. It may be that themodification is a result of complexing of the boron trifluoride with thealumina, or on thelothe'r hand, it maybe that the boron trifluoridereacts with residual hydroxyl groups on the alumina surface. lt has'been found at any particular preselectedtemperaturefor' treatment ofsubstantially anhydrous: alumina, utilizing:

either the gammaor theta-.aluminamodifications asset forth hereinabove,that the fluorine content of the treated. alumiuas attains a maximumwhich is not increased by further p sag of c onitrifiu id ove the arn=-M L. n4

maximum fluorine or boron trifluoride content of the alumina increaseswith temperature and depends upon the specific alumina selected. Asstated hereinabove, the alumina treatment is, in the preferredembodiment, carried out at a temperature equal to or just greater thanthe selected reaction temperature so that the alumina will notnecessarily tend to be modified further by the boron trifluoride whichmay be added in amounts not more than 0.8 gram per gram mol ofolefin-acting compound during the process and so that control of thearomatic hydrocarbon alkylation reaction is attained more readily. Inany case, the alumina resulting from any of the above mentioned borontrifluoride treatments is referred to herein in the specification andclaims as boron trifluoride modified substantially anhydrous alumina.

Alumina is not the only inorganic oxide which is modified by borontrifluoride as hereinabove described. Other suitable inorganic oxideswhich are substantially but not completely anhydrous and which are to atleast some degree modified by boron trifluoride include such varioussubstances as silica, titanium dioxide, zirconium dioxide, chromia, zincoxide, magnesia, calcium oxide, silicaalumina, silica-magnesia,silica-alumina-magnesia, silicaalumina-zirconia, chromia-alumina,alumina-boria, silicazirconia, etc. It is necessary that the inorganicoxide utilized form a fairly stable compound with boron trifluoride fromwhich the latter is not readily driven off by heat or reduced pressure.f the above mentioned inorganic oxides, substantially but not completelyanhydrous alumina is preferred, and particularly, synthetically preparedalumina of a high degree of purity consisting of substantially anhydrousgamma-alumina or substantially anhydrous theta-alumina.

This boron trifluoride modified alumina is utilized, as set forthhereinabove, along with not more than 0.8 gram of boron trifluoride pergram mol of olefin-acting compound. When the quantity of borontrifluoride modified alumina, along with boron trifluoride, is thatneeded for catalysis of the herein described reaction, the reactiontakes place readily. When the desired reaction has been completed, therecovered boron trifluoride modified alumina is free flowing and changedsolely from its original white color to a very light yellow color. Ofcourse, the alumina contains quantities of boron and fluorine byanalysis corresponding to that which will complex or react with thealumina in the manner described hereinabove under the temperatureconditions utilized for the reaction.

As set forth hereinabove, the present invention relates to a process forthe alkylation of an alkylatable aromatic hydrocarbon with anolefin-acting compound in the presence of a catalyst comprising a borontrifluoride modified substantially anhydrous inorganic oxide, andparticularly in the presence of a catalyst comprising not more than 0.8gram of boron trifluoride per gram mol of olefin-acting compound and aboron trifluoride modified substantially anhydrous alumina. Manyaromatic hydrocarbons are utilizable as starting materials in theprocess of this invention. Preferred aromatic hydrocarbons aremonocyclic aromatic hydrocarbons, that is, benzene hydrocarbons.Suitable aromatic hydrocarbons include benzene, toluene, ortho-xylene,meta-Xylene, para-xylene, ethylbenzene, ortho-ethyltoluene,meta-ethyltoluene, paraethyltoluene, l,2,3,-trimethylbenzene,1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene or mesitylene, normalpropylbenzene, isopropylbenzene, etc. Higher molecular weightalkylaromatic hydrocarbons are also suitable as starting materials andinclude aromatic hydrocarbons such as are produced by the alkylation ofaromatic hydrocarbons with olefin polymers. Such products are frequentlyreferred to in the art as alkylate, and include hexylbenzene,nonylbenzene, dodecylbenzene, pentadecylbenzene, hexyltoluene,nonyltoluene, dodecyltoluene, pentadecyltoluene, etc. Very oftenalkylate is obtained as a high boiling fraction in which the alkyl groupatta'ched to the aromatic nucleus varies in size from about C to about COther suitable alkylatable aromatic hydrocarbons include those with twoor more aryl groups such as diphenyl, diphenylmethane, triphenyl,triphenylmethane, fluorene, stilbene, etc. Examples of other alkylatablearomatic hydrocarbons within the scope of this invention as startingmaterials containing condensed benzene rings include naphthalene,alpha-methylnaphthalene, beta-methylnaphthalene, anthracene,phenanthrene, naphthacene, rubrene, etc. Of the above alkylatablearomatic hydrocarbons for use as starting materials in the process ofthis invention, the benzene hydrocarbons are preferred, and of thepreferred benzene hydrocarbons, benzene itself is particularlypreferred.

Suitable olefin-acting compounds or alkylating agents which may becharged in the process of this invention include monoolefins, diolefins,polyolefins, acetylenic hydrocarbons, and also alkyl chlorides, alkylbromides, and

alkyl iodides. The preferred olefin-acting compounds are olefinichydrocarbons which comprise monoolefins having one double bond permolecule and polyolefins which have more than one double bond permolecule. Monoolefins which may be utilized as olefin-acting compoundsor alkylating agents for alkylating alkylatable aromatic hydrocarbons inthe presence of the hereinabove described catalyst are either normallygaseous or normally liquid and include ethylene, propylene, l-butene,Z-butene, isobutylene, and higher normally liquid olefins such aspentenes, hexenes, heptenes, octenes, and higher molecular weight liquidolefins, the latter including various olefin polymers having from about6 to about 18 carbon atoms per molecule such as propylene trirner,propylene tetramer, propylene pentamer, isobutylene dimer, isobutylenetrimer, isobutylene tetramer, etc. Cycloolefins such as cyclopentene,methylcyclopentene, cyclohexene, methylcyclohexene, may be utilized, butgenerally not under the same conditions of operation applying tonon-cyclic olefins. The polyolefinic hydrocarbons utilizable in theprocess of this invention include conjugated diolefins such as butadieneand isoprene, as well as non-conjugated diolefins and other polyolefinichydrocarbons containing two or more double bonds per molecule. Acetyleneand homologs thereof are also useful olefin-acting compounds.

As stated hereinabove, alkylation of the above alkylatable aromatichydrocarbons may also be efiected in the presence of the hereinabovereferred to catalyst by reacting aromatic hydrocarbons with certainsubstances capa-' ble of producing olefinic hydrocarbons, orintermediates thereof, under the conditions of operation chosen for theprocess. Typical olefin producing substances capable of use includealkyl chlorides, alkyl bromides, and alkyl iodides capable of undergoingdehydrohalogenation to form olefinic hydrocarbons and thus containing atleast two carbon atoms per molecule. Examples of such alkyl halidesinclude ethyl chloride, normal propyl chloride, isopropyl chloride,normal butyl chloride, isobutyl chloride, secondary buty chloride,teritary butyl chloride, amyl chlorides, hexyl chlorides, etc., ethylbromide, normal propyl bromide, isopropyl bromide, normal butyl bromide,isobutyl bromide, secondary butyl bromide, tertiary butyl bromide, amylbromides, hexyl bromides, etc., ethyl iodide, normal propyl iodide, etc.

As stated hereinabove, olefin hydrocarbons, especially normally gaseousolefin hydrocarbons, are particularly preferred olefin-acting compoundsor alkylating agents for use in the process of the present invention. Asstated, the process can be successfully applied to and utilized forconversion of olefin hydrocarbons when these olefin hydrocarbons arepresent in minor quantities in gas streams.

Thus, in contrast to prior art processes, the normally gases ous olefinhydrocarbon for use in the process of the pres--- ent invention, neednot be purified or concentrated. Such; normally gaseous olefinhydrocarbons appear in minor: concentrations in various, refinery gasstreams, usually; diluted with various unreactive gases such. ashydrogen,

7 nitrogen, methane, ethane, propane, etc. These gas streams.containingzminor quantities of olefin hydrocarbon -are obtained inpetroleum refineries from various refinery installations includingthermal cracking units, catalytic cracking units, thermal reformingunits, coking units, polymerization units, etc. Such refinery gasstreams have in the .past often been burned for fuel value since aneconomical process for their utilization as alkylating agents orolefin-acting compounds has not been available except whereconcentration of the olefin hydrocarbons hasbeen carried outconcurrently therewith. This is particularly true for refinery gasstreams containing relatively minor quantities of olefin hydrocarbonssuch as ethylene. Thus, it has been possible catalytically to polymerizepropylene and/ or various butenes in refinery gas streams but theoff-gases from such processes still contain ethylene. Prior to ourinvention it has been necessary to purify and concentrate .this ethyleneor to use it for fuel. These refinery gas streams containingminorquantities of olefin hydrocarbons are known as off-gases. In addition tocontaining minor quantities of olefin hydrocarbons such as ethylene,propylene, and the various butenes, depending upon their source, theycontain varying quantities of nitrogen, hydrogen, and various normallygaseous paraffinic hydrocarbons. Thus, a refinery off-gas ethylenestream may contain varyingquantities of hydrogen, nitrogen, methane, andethane with the ethylene in minor proportion, while a refinery off-gaspropylene stream is normally diluted with propane and contains thepropylene in minor quantities, and a refinery off-gas butene stream isnormally diluted with butanes and contains the butenes in minorquantities. A typical analysis in mol percent for a utilizable refineryoff-gas from a catalytic cracking unit is as follows: nitrogen, 4.0%;carbon monoxide, 0.2%; hydrogen, 5.4%; methane, 37.8%; ethylene, 10.3%;ethane, 24.7%; propylene, 6.4%; propane, 10.7%; and C hydrocarbons,0.5%. It is readily observed'that the total olefin content of this gasstream is 16.7 mol percent and the ethylene content is even lower,namely 10.3 mol percent. Such gas streams containing olefin hydrocarbonsin minor or dilute quantities are particularly preferred alkylatingagents or olefin-acting compounds within the broad scope of the presentinvention. It is readily apparent that only the olefin content of suchgas streams undergoes reaction in the process of this invention, andthat the remaining gases free from olefin hydrocarbons are .vented fromthe process.

In accordance with-the process of the present invention, the alkylationof allrylatable aromatic hydrocarbons with olefin-acting compoundsreaction to produce alkylated aromatic hydrocarbons of higher molecularweight than those charged to the process .is effected in the presence ofthe above indicated catalyst at a temperature of from about C. or lowerto about 300 C. or higher, and preferably from about 20 to about 230 0,although the exact temperature needed for a particular aromatichydrocarbon alkylation reaction will depend upon the alkylatablearomatichydrocarbon and olefin-acting compound employed; The alkylation reactionis usually carried out at a pressure of from about substantiallyatmospheric to about 2.00 atmospheres. The pressure utilized is usuallyselected to'maintain the alkylatable aromatic hydrocarboninsu'bstantially liquid phase. Within the above temperature and pressureranges, it is not always possible to maintain the olefin acting compoundin liquid phase. Thus, when utilizing a refinery off-gascontaining minorquantities of ethylene, the ethylene will be dissolved in the liquidphase alkylatable aromatic hydrocarbon to the extent governed bytemperature, pressure, and solubility considerations. However, a portionthereof undoubtedly willbe in the gas phase. When possible, it ispreferred to maintain all-of the reactants in liquid phase. Such is notalways possible, however, as set forth hereinabove. Referring to thearomatic hydrocarbon subjected to alkylationa'it-istpreferable to -havepresent from 2m or more,

sometimes upto 20, molecularproportions of 'alkylatable aromatichydrocarbon per one molecular proportion .of olefin-acting compoundintroduced therewith to the alkylation zone. The higher molecular ratiosof alkylatable aromatic hydrocarbon to olefin are particularly necessarywhen the olefin employed in the alkylation process is a highmolecularweight olefin boiling generally higher than pentenes, sincethese olefins frequently undergo depolymerization prior to orsubstantially simultaneously with alkylation so that one molecularproportion of such an olefin can hus alkylate two or more molecularproportions of the akylatable aromatic hydrocarbon. The higher molecularratios of alkylatable aromatic hydrocarbon to olefin-also tend to reducethe formation of polyalkylated products because of the operation of thelaw of mass action under these conditions.

In converting aromatic hydrocarbons to effect alkylation thereof withthe type of catalysts herein described, either batch or continuousoperations may be employed. The actual operation of the process admitsof some modification depending upon the normal phase of the reactingconstituents, Whether the catalyst utilized is not more than 0.8 gram ofboron trifluoride per gram mol of olefinacting compound along with aboron trifiuoride modified alumina, or said boron trifluoride modifiedalumina alone, and whether batch or continuous operations are employed.In one type of batch operation, an aromatic hydrocarbon to beallrylated, for example benzene, is brought to a temperature andpressure within the approximate range specified in the presence of acatalyst comprising boron trifluoride and boron trifiuoride modifiedsubstantially anhydrous gamma-alumina having a concentrationcorresponding to a sufficiently high activity and alkylation of thebenzene is effected by the gradual introduction under pressure of anolefin such as ethylene, in a manner to attain contact of the catalystand reactants and in a quantity so that the amount of boron trifluorideutilized is from about 0.001 gram to about 0.8 gram per gram mol-ofolefin. .After a sufiicient time at the desiredtem perature andpressure, the gases, if any, are vented and the alkylated aromatichydrocarbon separated from the reaction products.

In another manner of operation, the aromatic hydrocarbon maybe mixedwith the olefin at a suitable temperaturein the presence of sufficientboron trifluoride modified alumina, and boron ,trifluoride is then addedto attain an amount between from about 0.001 gram to about 0.8 gram pergram mol of olefin. Then, reaction is induced by sufficiently longcontact time with the catalyst. Alkylation may be allowed to progress todifferent stages depending upon contact time. In the case of thealkylation of benzene with normally gaseous olefins, the most desirableproduct is that obtained by the utilization in the process of molarquantities of benzene exceeding those of the olefin. In a batch type ofoperation, the'amount of boron trifluoride modified alumina utilizedwill range from about 1% to about 50% by weight based on the aromatichydrocarbon. With this quantity of boron trifluoride modified alumina,and boron trifluoride as set forth hereinabove, the contact time may bevaried from about 0.1 to about .25 hours or more. Contact time is notonly dependent upon the quantity of catalyst utilized but also upon theefliciency of mixing, .shortercontact times being attained by increasingmixing. After batch treatment, the boron trifluoride component ofthecatalyst is removed in any suitable manner, such as by venting orcaustic washing, the organic layer or fraction is detrifluoride modifiedalumina. The olefin-acting compound may be added to the aromatichydrocarbon stream prior hydrocarbon reactant will vary from about 0.25to about 20 or more. The details of continuous processes of this generalcharacter are familiar to those skilled in the alkylation of aromatichydrocarbons art and any necessary additions or modifications of theabove general procedures will be more or less obvious and can be madewithout departing from the broad scope of this invention.

The process of the present invention is illustrated by the followingexamples which are introduced for the purpose of illustration and withno intention of unduly limiting the generally broad scope of thisinvention.

EXAMPLE I This example illustrates the efiectiveness of the process ofthe present invention utilizing a catalyst comprising a borontrifluoride modified substantially anhydrous theta-alumina for thealkylation of benzene with ethylene containing various inert diluents.The experiments were conducted in a once-through bench scale processingunit consisting of'liquid and gas charge pumps, reaction tube, highpressure gas separator, pressure controller, and liquid and gascollection systems. The reactor eifiuent was collected in the highpressure separator at reactor pressure. Boron trifluoride was meteredinto the recubic centimetcr per gram; pore diameter, 177 A.; andapparent bulk density, 0.725 gram per milliliter. Sixty milliliters(43.5 grams) of the theta-alumina was charged to the reactor.

The benzene utilized in the following experiments was dried in storageover calcium chloride. The composition of the synthetic elf-gas feed isas follows: 25.2 mol percent nitrogen, 0.2 mol percent carbon monoxide,25.3 mol percent hydrogen, 27.6 mol percent methane, 21.3 mol percentethylene, and 0.4 mol percent ethane. Prior to contacting thetheta-alumina with the hydrocarbons, the reactor containing thetheta-alumina was slowly pressured to 50 p.s.i.g. with 6 grams of borontrifluor-ide.

A temperature wave, increasing fromthe ambient temperature up to about58 C., traveled through the alumina bed during this initial addition ofthe boron trifiuoride; The boron trifluoride was in contact with thetheta-alumina for a time of about one hour. Then, the reactiontemperature was increased to 150 C., and the ethylene feed was pressuredinto the reactor to the pump intake pressure (400 p.s.i.g.). Thereafter,both the benzene and ethylene pumps were started, the reactor pressurewas increased to the 500 p.s.i.g. operating pressure, and the input ofboron trifluoride was started. The operating conditions utilizedincluded a temperature of 150 C., a pressure of 500 p.s.i.g., a benzeneto ethylene mol ratio of about 5.5, and a benzene liquid hourly spacevelocity of about 1.5. The boron trifluoride input was varied from 1.5grams per gram mol of ethylene down to 0.20 gram per mol of ethylene.The operating conditions utilized and the results obtained in a 210 hourrun are summarized in the following Table: I:

Table l ALKYLATION OF BENZENE WITH SYNTHETIC GAT-ORAOKER OFF-GAS IN THEPRESENCE OF BF; AND

BFs-MODIFIED THETA-Aho l Accumulated Hours 18-45. 8 45. 8-73. 8 73.8-92. 8 92. 8116 177. 44409. 4 Dilueuts ll] 02H; Feed NZ+H2+CHA SolidCatalyst Component..- BF; modified theta-A1103 BFa Input, gins/mol C2H4charged 1. 0.88 0.45 0. 20 0. 54 Benzene/C2134, M01 Ratio. 5. 2 5. 6 5.5 5. 3 5. 3 Temperature, C... 160 150 150 150 150 Pressure. p Si! 500500 500 500 500 Charge Rates, ml./hr.:

Benzene 90 90 90 90 90 CzH4 Stream 500 p.s.i.g.-H O 875 875 875 875 875LHSV, Benzene. 1. 60 1. 50 1. 60 1. 60 1. 50

p Charge High Pressure Separator Gas, M01 percent:

Na 25. 2 36. 7 34. 9 34. 4 32. 8 36. 4 CO. 0.2 0.2 0.2 0.3 0.5 0 H 25. 325. 8 28. 2 30. 6 32. 9 29. 1 U 4. 27. 6 33.1 32. 9 32.4 32. 6 32. 5 2 421. 3 Tr Tr 0 0 1. 2 zHa. 0. 4 5. 0 3. 5 2. 0 0. 9 0. 4 CsHc 0 0.2 0.30.3 0.3 0.4 Ethylene reacted, Wt. Percent. 99. 8 99. 8 09. 8 99. 8Product Yield, gms./gm. 01H. charged:

Ethylbenzene 1. 73 1. 82 2. 04 Diethylbenmn 0. 34 0. 33 0. 41 HigherBoilin 0. 19 0. 19 0.21 Product Yield, gins/gm. OsHa charged:Ethylbenzene 1. 61 1. 85 1. 30 Ethylbenzene, Ultimate Yield:

gmsJgm. CQHA 2.34 2.42 2.78 Percent of Theory- 62 64 74 action systemcontinuously from a charger under pressure.

The reaction tube was charged with substantially anhydrous theta-aluminaprepared from ,4 diameter alumina spheres. The alumina spheres weredried for 17 hours at 200 C. and then calcined at 1200 C. for two hours.X-ray difiraction analyses indicated the resulting material to besubstantially all theta-alumina. The thetaalumina had the followingphysical properties: surface area, 53 square meters per gram;

P me, 0.234 75 was converted to ethane.

From the above table it is observed that at a boron trifluoride additionrate ofl.50 grams of boron trifluoride per gram of ethylene, all of theethylene was removed from the charge gas. At this boron trifluorideaddition rate, the once-through yield ofethylbenzene was 1.73 grams pergram of ethylene charged. Some of the ethylene went to formdiethylbenzene, the yield of which was 0.34 gram per gram of ethylene.The ethylene which was not accounted for as alkylaromatic hydrocarbonsAbout 5.0 mol percent ethane was found in the high "pressure separatorgas. A substantial reduction in hydrogen concentration occurredsimultaneously. In going from Test 1 to Test 2, as the amount of boron'trifluoride input was decreased from 1.50 grams of boron trifluoride to0.88 gram of boron trifiuoride per gram mol of ethylene charged, lessethane was produced and a greater yield of ethylbenzene and higherboiling alkyl aromatics was observed. Then in going from Test 2 to Test3, reducing the amount of boron trifluoride further to 0.45 gram ofboron 'trifluoride per gram mol of ethylene decreased the ethaneproduction (and increased the yield of ethylbenzene). In going from Test3 to Test 4, further reduction of the boron trifluoride input to 0.20gram per gram mol of ethylene, reduced the ethane content of the highpres sure separator gas to a value equivalent to its original content ofthe feed, along with a simultaneous increase in yield of ethylbenzene.Test 5 shows that at the end of 210 hours on stream the weight percentethylene reacted was still 99% and the ethane contentof thehigh'pressure separator gas was the same as the gas feed.

Infrared analyses of the 130-440 C. fractions of the liquid productsindicated 100% ethylbenzene; no other absorption bands due to C -Caromatics were detected. Organic fluoride content of these ethylbenzenefractions was less than 10 p.p.m. As shown in Table I, the amount ofdiethylbenzenes increased with the yield of ethylbenzene fraction. Thesediethylbenzenes can be recycled to obtain alkyl transfer and thusincrease the ultimate yield of ethylbenzene.

' These data show that the completeness of ethylene removal from theoff-gas is dependent upon the input of boron trifluoride. If too muchboron trifluoride is employed, ethylene is converted to ethane and thusthe ultimate yield of ethylbenzene is reduced. When the gas stream of21.4% concentration is supplied to the reaction zone under the sameconditions shown in this example, but without any introduction of borontrifluoride into the reaction zone, conversion to alkylated aromaticsdrops off. .At favorable conditions, Test 4, where the boron trifluorideinput was 0.20 gram per gram mol of ethylene and Where a 2.04 gram yieldof ethylbenzene fraction was obtained per gram of ethylene charged,0.007 gram of boron trifluoride were fed per gram of ethylene charged.

This is equivalent to an input of 0.0034 gram of boron.

trifluoride per gram of ethylbenzene produced. Appreciably all of theboron trifluoride input can be recovered from the reactor effluent.

The recovered theta-alumina after about 210 hours of operation was freeflowing and changed from a white to a light yellow color. Based on theweight of the used alumina, the normal pentane soluble content of thealucharged reacted with the benzene.

mina equalled 0.52% and the ether soluble material,

after hydrolysis, equalled 0.10%.

Under the above described operating conditions, benzene consumptionamounted to about 1.2 mols per mol of ethylbenzene produced. This figureis based upon the difference between benzene charged and recovered andable ratioof benzeneto ethylene, namely about 7 to 10 instead'of thepresent 5, increases monoalkylation and reduces benzene consumption. Asstated above, recycle of the polyethylbenzene fraction to the reactorfor alkyl transfer also reduces benzene consumption.

EXAMPLE II This exampleillustrates the alkylation of benzene with asynthetic off-gas similar to that normally observed from a catalyticcracking unit. This experiment was carried out with a catalystcomprising from about 0.52 to about 0.74- gram of boron trifluoride pergram mol of olefin and in the presence of a boron trifluoride modifiedgamma-alumina. The once-through bench scale processing unit described inExample I was also utilized thus a small error due to benzene loss invarious portions of the apparatus magnifies the quantity. 'A morefavortrifluoride was added to the reactants in this example asa 15-16%mixture in dry nitrogen.

The reaction tube was charged with gamma-a1umina prepared from $4diameter alumina spheres. The alumina spheres were dried 117 hours at220C. and calcined at 680 C. for two hours. X-ray diffraction analysesindicated the resulting material to be substantially anhydrousgamma-alumina. This gamma-alumina had the following physical properties:surface area, 181 square meters per gram; pore volume, 0.650 cubiccentimeter per gram; pore diameter, 144 A.; and apparent bulk density,0.490 gram per milliliter. Sixty milliliters (29.4 grams) ofgamma-alumina were charged to the reactor.

The benzene utilized inthis experiment was dried over calcium chloride.The composition of the synthetic ofigas feed is as follows: carbondioxide, 0.1 mol percent; nitrogen, 29.0-mol percent; carbon monoxide,1.3 mol percent; hydrogen, 18.9 mol percent; methane, 35.0 mol percent;ethylene, 12.0 mol percent; ethane, 0.5 mol percent; propylene, 2.5 molpercent; propane, 0.1 mol percent; isobutane, 0.1 mol percent; andacetylene, 0.5 mol percent. Prior to contacting of the gamma-aluminawith the hydrocarbons, the reactor containing the gammaalumina wasslowly pressured to 50 p.s.i.g. with 5 grams of boron trifiuoride. Atemperature wave, an increase from room temperature up to about 170 C.,traveled through the alumina bed during the initial addition of theboron trifluoride. The'boron trifiuoride was in contact with thegamma-alumina for one hour. Then the reaction temperature wasincreasedto 150 C. and the operation commenced. The operating conditionsutilized included a temperature of 150 C., a pressure of 600 p.s.i.g., abenzene to olefin mol ratio of 7.78, and a benzene liquid hourly spacevelocity of about 1.5. The boron trifluoride input which was startedjust prior to addition of the hydrocarbons varied from 0.52 grain to0.74 gram per gram mol of olefin. Since the feed gas inthis examplecontained ethylene, propylene, and acetylene, the aromatic to olefinratio and the quantity of boron trifluoride input have taken this totalunsaturation mto' account.

The experiment was continued for about 96.5 hours during which time 7523grams of benzene were charged. Taking only the olefin content of the gasfeed into account, there was charged during this same time 289.8

grams of ethylene, 90.4 grams of propylene, and 11.2 grams of acetylene.

The total weight of reactants charged was 7914.4 grams. During this 96.5hours, the vent gas was free from unsaturated hydrocarbons, in otherwords, all of the ethylene, propylene, and acetylene Over the 96.5 hourperiod there was recovered 7098 grams of reactor efiiuent Qin thelowpressure separator and the vent gases containing 739 grams of benzene,giving a recovery of 7337 Q grams or ustover'99 weight percent recovery.

The plant liquid efiluent was tested for unsaturation and found to'havea bromine index of 5, indicating the substantial absence of olefinpolymerization products. Ethylbenzene was produced in the quantity of2.44 grams 'per'gram of ethylene charged representing 64.4% of the"theoretical yield on a once-through basis.

I There was also obtained 0.39 gram of diethylbenzene per gram ofethylbenzene charged. Taking into account recycling of thisdiethylbenzene, the ultimate yield of ethylbenzene based upon ethylenecharged is 85.2% of the theoretical quantity. Cumene was produced in thequantity of 2.16

grams per gram of propylene charged representing a 75.8% theoreticalyield on a once-through basis. There was also produced 0.10 gram ofdiisopropylbenzene per gram of propylene charged. propylbenzene is takeninto account for recycle purposes,

there is attained an ultimate yield of cumene.of.82.6% of thetheoretical quantity. At the same time, 6.45 grams.

of 1,1-diphenylethane were produced per gram of acet- If this amount ofdiiso gram to about 0.8 gram per gram'mol of olefin charged.

EXAMPLE fut This example illustrates the alkylation of benzene with adilute. gas stream in the presence of about 0.1 gram of borontrifluoride per gram mol of olefin; The reaction tube was again packedwith boron trifluoride modified gamma-alumina. The same once-throughbench scale processing unit described in' Example I was also Borontrifluoride was added to the reactants in this example as a 3 mixture indry nitrogen.

The reaction tube was charged with 60 (29.4 grams) of the samegamma-alumina described in Example II. This gamma-alumina had the samephysical properties as set forth hereinabove. The benzene utilized inthis experiment was dried over calcium chloride. The composition of thedilute olefin stream is as follows: nitrogen, 83.3 mol percent;ethylene, 13.5 mol percent; and propylene, 3.2 mol percent.' Prior tothe contacting '15 utilized for the experiment desgribedin thisexample.

, gamma-alumina as the catalyst at hourly liquid space,

milliliters was within experimental error. Complete olefin conversionwas obtained in each of the tests although a changein the type ofproducts produced was observed with increasing space velocity,particularly in relation to the ethylbenzene product. version ofethylene to ethylbenzene was about 73-74% in Tests 6 and 7 at benzeneliquid hourly space velocities of 0.75 and 1.5 but decreased to about60% as the space velocity was raised further to 2.5. Higher ultimateyields of monoalkylated aromatic hydrocarbons can be produced, as setforth hereinabove, by recycle of diand polyalkyl compounds.

Theabove results indicate satisfactory conversion to alkylaromatichydrocarbons by the process of this invention utilizing extremely smallquantities of boron trifluoridein conjunction with boron trifluoridemodified velocities most economical for commercial operation.

7 EXAMPLE 1v This example illustrates the alkylation of benzene withethylene and propylene diluted with an inert gas.

, p This experiment was carried out in an effort to determine,

of the gamma-alumina with the hydioeaib'oas, the reactor containing thegamma-alumina was slowly pressured to 50 p.s.i.g. with 5 grams of borontrifluoride. A temperature wave traveled through the alumina bed duringle initial addition of the boron trifluoride with a peak temperature ofabout 150 C. being attained. The boron trifluoride was in contact withthe gamma-alumina for one hour. Then, heat input to the reaction tubewas commenced and a processing operation started.- The operatingconditions utilized includeda temperature of 125 C, a pressure of 600p.s.i.g., a benzene toolefirrmol ratioof about 7:1, and a benzene liquidhourly space velocity varying from 0.75'to 2.5. The boron trifluorideinput which was started just prior'to the input of the hydrocarbonsvaried from 0.109 to 0.125 gram per gram summary of three tests carriedout at these varying hourly liquid space velocities is'presented in thefollowing Table H: TableII' LI KTLATION OF BENZENE .WITI'I .OiL EFIN SlDILUTED WITH NITROGEN IN THE PRESENCE OF BF; AND BFsamong other things,the optimum minimum quantities of boron trifluoride which could beutilized as added boron trifluoride when processing over a solidcatalyst component comprising boron trifluoride modified gamma-"alumina. The same once-through bench scale processing unit described inExample I was utilized for the experiment described in this example. Asin Example III, the boron trifiuoride was added as a 3% mixture in drynitrogen. t

' The reaction tube was charged with 30 milliliters (14.7 grams) ofanother sample of the gamma-alumina described in Example 11. Thisgamma-alumina had the same physical properties as set forth hereinabove.

The benzene utilized in this experiment was again dried over calciumchloride. The composition of the dilute olefin stream utilized as thealkylating agent for Tests 9 through 11 is as follows: nitrogen, 85.7mol percent; ethylene, 11.7 mol percent; and propylene, 2.6 mol percent.In Tests 12 through 14 this composition varied slightly to thefollowing: nitrogen, 85.1 mol percent;.

ethylene, 12.0 mol percent; and propylene, 2.9 mol percent. Prior to thecontacting of the gamma-alumina with the hydrocarbons, the reactorcontaining the gammaalumina was slowly pressured to 50 p.s.i.g. with 2.5grams of boron trifluoride. A temperature wave traveled through thealumina bed during the initial addition of the boron trifluoride and apeak temperature of about 150 0.149 down to 0.011 gram of borontrifluoride per gram based upon the mols of olefin in the feed. Incontrast to the test described in Example III, these tests show verylittle further decrease in monoethylbenzene produc- MODIFIEDGAMMA-ALUMINA TCSt' 6 7 8 Accumulated Hours. 36438 76-96 108-123 SolidCatalyst Component.; BF h/[odified Gamma:

' Alumina BF; Input, gms./mol olefin 0. 109 0. 119 0. 125

Benzene/Olefin, mol ratio. 6.82 6. 6. 65

Temperature, "C 125 125 125 LHSV, Benzene 0.75 1. 48 2. 47 1 Charge, gns;

Ethylene 67.1 85. 7 Propylene"- 23.9 30. 5 Benzene .4. 1', 561.3 1, 963.2

Total; 1, 342, 9 1, 652.3 2, 079. 4

Recovery, gms.:

Unreacted olefin 0 0 0 Hydrocarbons 1, 330. 2 1, 649. 9 2, 102. 2

Weight Percent Recovery 99. 1 99. 9 101. 1

Results;

Ethylene Conversion, Percent 100 100 Propylene Conversion, Percent.. 100100 100 Converted Ethylene, Percent Recov- I ered as: r I Ethylbenzene p73.1 74. 0 59. 5 Diethylbenzene 19.6 18.4 19.8 j Polyethylbenzene 7.37.6 20. 7 Converted Propylene, Percent Recovered as:

' Gumene 92.7 91.4 92.5

Diand Polypropylbenzene 7. 3 8.6 7. 5

tion with increasing space velocity. This same observation can also bemade for the yields of cumene and of diand polyalkylated alkylaromatichydrocarbons. The weight percent recoveries in each of the above testswas within experimental error as is true for Tests 12 14 in the table.

The once-through con through Table 111 ALKYLATION OF BENZENE WITHOLEFINS DILUTED WITH 'NITROGEN IN THE PRESENCE OF BFa AND BFa-MODIFIEDGAMMA-ALUMINA Test. 9 1O 11 12 13 14 Accumulated Hours 2161 75-93101-117 125-141 149-165 173-1 89 Solid Catalyst Component. BFs-ltiodified C amma-Alumina BF; Input, gms/mol olefin 0. 106 149 0.122 0.0550.025 0. 011 Benzene] Olefin, moi ratio. 7. 80 7. 76 7. 99 7. 67 7. 607. 71 Temperature, C 125 125 125 125 125 125 LHSV, Benzene 2. 51 3. 987. 99 7. 92 '7. 93 7.93

Charge, gms.: v

Ethylene 100. 0 71. 8 123. 9 126. 1 127. 6 125. 4

Propylene. 3S. 3 24. 1 41. 6 46. .46. 6 46. 4

Benzene '2, 652. 5 1. 897. 4 3, 374. 9 3, 354. 7 3, 356.0 3, 357.8

Total 2, 785. 8 1. 993. 3 3, 540. 4 3, 527.3 3, 5,30. 2 3.529. 6

Recovery, gins:

Unreacted olefin. 0. 4 1. 0 2.0 1.0 2.3

"Hydrocarbons 2, 789. 9 2,008.5 3, 559. 1 3, 569. 2 3, 571. 4 3,564. 7Weight Percent Recovery 100. 8 100. 5 101.2 101. 2 101.0 Results:

Ethylene Conversion, Percent 100 99. 4 99. 2 98:4 9912' 98:2

Propylene Conversion, Percent 100 100 100 100 (100 100 Con ertedEthylene, Percent Recovered as: l

E thylbenzene 60. 0 57. 1 60. 2 62. 2 57. 4 63.9

'Diethylbenzene... 23.0 21.3 18. 1 20. 3 17. 8 19. 6

Polyethylbenzene l7. 0 21. 6 21. 7 17. 5 v24. 8 16.5 ConvertedPropylene, Percent Rec Oumene. 88. 5 83. 6 92. 6 84. 8 87.9 85. 6

Diand Polypropylhenzene. 11. 5 16. 4 7. 4 15. 2 12. 1 14. 4

As set forth hcreinabove, the analysis of the gas feed in Tests 12through 14 was somewhat difierent than in Tests 9through 11. Test 12differs from Test 11 in that the boron tri-iluoride input is about cutin half. Substantially the same results were still obtained. in Test 13the boron trifluoride input was again out in half and the resultsapparently remain constant. In Test 14- the boron trifluoride input wasagain cut in half from the previous test, down to 0.011 gram per grammol of olefin, and the olefin conversion remained complete. Thisoperation includes olefin conversion at a steady rate, and production ofmonoand dialkylaromatic hydrocarbons in substantially the same amountsas with larger quantities of boron trifiuoride. The yields basedupon-the weight percent recovery in these three tests were also withinexperimental error.

When no boron trifluoride is added, some unreacted olefins begin toappear in the vent gases .from the plant and conversion to desiredproducts drops 011. This is indicative of the necessity for an amount ofboron trifluoride addition of not more than 0.8 gram per gram mol ofolefin. When this amount of boron trifluoride addition is exceeded, asshown in Example I, olefin conversion to other products such asparafiins occurs.

We claim as our invention:

L'A process for the production of an alkylaromatic hydrocarbon whichcomprises passing to an alkylation zone containing boron triiluoridemodified substantially anhydrous alumina selected from the groupconsisting of gamma-alumina and theta-alumina, alkylatable aromatichydrocarbon, olefin-acting compound, and not more than 0.8 gram of borontriiluoride per gram mol of olefin-acting compound, reacting thereinsaid alltylatable aromatic hydrocarbon with sm'd olefin-acting compoundat, alkylation conditions in the presence of an 'alkylation catalystcomprising said boron trifiuori-de modified alumina, and recoveringtherefrom alltylated aromatic hydrocarbon.

2. A process for the production of an alkyl-aromatic hydrocarbon whichcomprises passing to an alkylation zone containing boron trifiuoridemodified substantially anhydrous gamma-alumina, alkylatable aromatichydrocarbon, olefin-acting compound, and not more than (1.8 gram ofboron trifluoride per gram mol of olefineacting compound, reactingtherein 1 said ,alkylatable aromatic hydrocarbon with said.olefinzacting compound at,al kyla-1' tion 'conditionsin the presence ofan .alkylation' catalyst comprising .said boron trifluofride ,modifiedgamma-aluj mine, and recoveringthereirom alkylated aromatic'hydrocarbon.

3. A processfor the production of an alkylearomatic hydrocarbon whichcomprises passing on an alkylatiou zone containing boron ,trifluoridemodified substantially anhydrous theta-alumina, alkylatable aromatic hydocarbon, olefin-acting compound, and not more than 0.8 gram of boron.trifluoride per gram .mol .otolefin-acting compound, reacting thereinsaid valkylatable aromatic hydrocarbon with said olefin-acting compoundat alkylamina, and recovering therefrom; alkylated aromatichydrocarbon;V

5. A process for {the production of 'an *alkyl aromatic hydrocarbonwhich comprises passing to an alkylation zone containing borontrifluoridemodified substantially anhydrous theta-alumina, .alkylatablearomatic hydro carbon, unsaturated hydrocarbomand from about '0.,00lgram to about 0.8.gram of borontrifluoridqper gram inol of unsaturatedhydrocarbon, reacting therein said ,allgylatable aromatic hydrocarbonwith said unsaturated hydrocarbon at ,alkylation conditions the presenceor an alkylation catalyst comprising said boron trifluoride modifiedtheta-alumina, andrecovering therefrom ,alkylated' aromatic hydrocarbon.

6. A process for the production ofan alkylaromatic' hydrocarbon whichcomprises :passingto alkylation ere.

17 zone containing boron trifluoride modified substantially anhydrousgamma-alumina, alkylatable aromatic hydrocarbon, olefin, and from about0.001 gram to about 0.8

gram of boron trifluoride per gram mol of olefin, reacting therein saidalkylatable aromatic hydrocarbon with said olefin at alkylationconditions in the presence of an alkylation catalyst comprising saidboron trifluoride and boron trifluoride modified gamma-alumina, andrecovering therefrom alkylated aromatic hydrocarbon.

7. A process for the production of an alkyl-aromatic hydrocarbon whichcomprises passing to an alkylation zone containing boron trifluoridemodified substantially anhydrous theta-alumina, alkylatable aromatichydrocarbon, olefin, and from about 0.001 gram to about 0.8 gram ofboron trifluoride per gram mol of olefin, reacting therein saidalkylatable aromatic hydrocarbon with said olefin at alkylationconditions in the presence of an alkylation catalyst comprising saidboron trifluoride and boron trifluoride modified theta-alumina, andrecovering therefrom alkylated aromatic hydrocarbon.

8. A process for the production of an alkyl-benzene hydrocarbon whichcomprises passing to an alkylation zone containing boron trifluoridemodified substantially anhydrous gamma-alumina, alkylatable benzenehydrocarbon, olefin, and from about 0.001 gram to about 0.8 gram ofboron trifluoride per gram mol of olefin, reacting therein saidallsylatable benzene hydrocarbon with said olefin at alkylationconditions in the presence of an alkylation catalyst comprising saidboron trifluoride and boron trifluoride modified gamma-alumina, andrecovering therefrom alkylated benzene hydrocarbon.

9. A process for the production of an alkyl-benzene hydrocarbon whichcomprises passing to an alkylation zone containing boron trifluoridemodified substantially anhydrous theta-alumina, alkylatable benzenehydrocarbon, olefin, and from about 0.001 gram to about 0.8 gram ofboron trifluoride per gram mol of olefin, reacting therein saidalkylatable benzene hydrocarbon with said olefin at alkylationconditions in the presence of an alkylation catalyst comprising saidboron trifluoride and boron tri fluoride modified theta-alumina, andrecovering therefrom alleylated benzene hydrocarbon.

10. A process for the production of ethylbenzene which comprises passingto an alkylation zone containing boron trifluoride modifiedsubstantially anhydrous gamma-alumina, benzene, ethylene, and from about0.001 gram to about 0.8 gram of boron trifluoride per gram mol ofethylene, reacting therein said benzene with said ethylene at alkylationconditions in the presence of an alkylation catalyst comprising saidboron trifluoride and boron trifluoride modified gamma-alumina, andrecovering therefrom ethyl-benzene.

211. A process for the production of cumene which comprises passing toan alkylation zone containing boron trifluoride modified substantiallyanhydrous gamma-alumina, benzene, propylene, and from about 0.001 gramto about 0.8 gram of boron trifluoride per gram mol of propylene,reacting therein said benzene with said propylene at alkylationconditions in the presence of an alkylation catalyst comprising saidboron trifluoride and boron trifluoride modified gamma-alumina, andrecovering therefrom cumene.

12. A process for the production of butylbenzene which comprises passingto an alkylation zone containing boron trifluoride modifiedsubstantially anhydrous gamma-alumina, benzene, a butene, and from about0.001 gram to about 0.8 gram of boron trifluoride per gram mol ofbutene, reacting therein said benzene with said butene at alkylationconditions in the presence of an alkylation catalyst comprising saidboron trifluoride and boron trifluoride modified gamma-alumina, andrecovering therefrom butylbenzene.

13. A process for the production of ethylbenzene which comprises passingtoan alkylation zone containing boron trifluoride modified substantiallyanhydrous thetaalumina, benzene, ethylene, and from about 0.001 grain toabout 0.8 gram of boron trifluoride per gram mol of ethylene, reactingtherein said benzene with said ethylene at alkylation conditions in thepresence of an alkylat-ion catalyst comprising said boron trifluorideand boron tri fluoride modified theta-alumina, and recovering therefromethylbenzene.

14. A process for the production of cumene which comprises passing to analkylation zone containing boron trifluoride modified substantiallyanhydrous thetaalum-ina, benzene, propylene, and from about 0.001 gramto about 0.8 gram of boron trifluoride per gram mol of propylene,reacting therein said benzene with said propylene at alkylationconditions in the presence of an alkylation catalyst comprising saidboron trifluoride and boron trifluoride modified theta-alumina, andrecovering therefrom cumene.

15. A process for the production of ethylbenzene which comprises passingto an alkylation zone containing boron' trifluoride modifiedsubstantially anhydrous gammaalumina, benzene, ethylene, and from about0.001 gram to about 0.8 gram of boron trifluoride per gram mol ofethylene, reacting therein said benzene with said ethylene at alkylationconditions including a temperature of from about 0 to about 300 C. and apressure of from about atmospheric to about 200 atmospheres in thepresence of an alkylation catalyst comprising said boron trifluoride andboron trifluoride modified gamma-alumina, and recovering therefromethylbenzene.

16. A process for the production of cumene which comprises passing to analkylation zone containing boron trifluoride modified substantiallyanhydrous gamma alumina, benzene, propylene, and from about 0.001 gramto about 0.8 gram of boron trifluoride per gram mol of propylene,reacting therein said benzene with said propylene at alkylationconditions including a temperature of from about 0 to about 300 C. and apressure of from about atmospheric to about 200 atmospheres in thepresence of an alkylation catalyst comprising said boron trifluoride andboron trifluoride modified gamma-alumina, and recovering therefromcumene.

17. A process for the production of butylbenzene which comprises passingto an alkylation zone containing boron trifluoride modifiedsubstantially anhydrous gammaalumina, benzene, a butene, and from about0.001 gram to about 0.8 gram of boron trifluoride per gram mol ofbutene, reacting therein said benzene with said butene at alkylationconditions including a temperature of from about 0 to about 300 C. and apressure of from about atmospheric to about 200 atmospheres in thepresence of an alkylation ,catalyst comprising said boron trifluorideand boron trifluoride modified gamma-alumina, and recovering therefrombutylbenzene.

18. A process for the production of ethy'lbenzene which comprisespassing to an alkylation zone containing boron trifluoride modifiedsubstantially anhydrous thetaalumina, benzene, ethylene, and from about0.001 gram to about 0.8 gram of boron trifluoride per gram mol ofethylene, reacting therein said benzene with said ethylene at alkylationconditions including a temperature of from about 0 to about 300 C. and apressure of from about atmospheric to about 200 atmospheres in thepresence of an alkylation catalyst comprising said boron trifluoride andboron trifluoride modified theta-alumina, and recovering therefromethylbenzene.

19. A process for the production of cumene which comprises passing to analkylation zone containing boron trifluoride modified substantiallyanhydrous thetaalumina, benzene, propylene, and from about 0.001 gram toabout 0.8 gram of boron trifluoride per gram mol of propylene, reactingtherein said benzene with said propylene at alkylation conditionsincluding a temperatnre of from about 0 to about 300 C. and a pressureof from about atmospheric to about 200 atmospheres in the presence of analkylation catalyst comprising said boron trifluoride and borontr-ifluoride modified theta-alumina, and recovering therefrom cumene.

I20 0 References Cited inthe file of this patent UNITED STATES PATENTS 72,584,103 I Pines et a1. Feb ..5, 1952 2,804,491 May et a1. ug. 27,1957

FOREIGN PATENTS. v

1,028,700 France May27,1953

1. A PRECESS FOR THE PRODUCTION OF AN ALKYLAROMATIC HYDROCARBON WHICHCOMPRISES PASSING TO AN ALKYLATION ZONE CONTAINING BORON TRIFLUORIDEMODIFIED SUBSTANTIALLY ANHYDROUS ALUMINA SELECTED FROM THE GROUPCONSISTING OF GAMMA-ALUMINA AND THETA-ALUMINA, ALKYLATABLE AROMATICHYDROCABRON, OLEFIN-ACTING COMPOUND, AND NOT MORE THAN 0.8 GRAM OF BORONTRIFLUORIDE PER GRAM MOL OF OLEFIN-ACTING COMPOUND, REACTING THEREINSAID ALKYLATABLE AROMATIC HYDROCARBON WITH SAID OLEFIN-ACTING COMPOUNDAT ALKYLATION CONSITIONS IN THE PRESENCE OF AN ALKYLATION CATALYSTCOMPRISING SAID BORON TRIFLUORIDE MODIFIED ALUMAINA, AND RECOVERINGTHEREFROM ALKYLATED AROMATIC HYDROCARBON.